Patent EA-001435-B1 (EA)
Title: Ultralight coaxial cigarette with including a multipart filter
Inventor: SCHNEIDER WERNER
IPC: A24D1/00
Filed: 1998-05-29
Abstract: 1. A coaxial cigarette comprising  a) a coaxial tobacco rod (20) comprising a rod core (22), a rod core wrapping (23), a rod jacket (21) and a rod jacket wrapping (24) and b) the ratio of the resistance to draw of said rod core (22) to the resistance to draw of said rod jacket is greater than unity and preferably in the range of 2 to 4, and c) a multi-part ventilated filter (10), characterized in that  d) said filter (10) comprises a filter wrapping (16) as well as at least two longitudinal segments of which at least one is a coaxial filter segment (13) having a core element (15), a core element wrapping (17) and a jacket element (14), and that  e) the resistance to draw of said coaxial filter segment (13) is in the range of 45 to 120 mm WC; g) said core element (15) consists of cellulose acetate, paper or Crest with a non-ventilated retention of 65 to 95%; h) said core element wrapping (17) is substantially impermeable to air; i) said jacket element (14) consists of cellulose acetate or other suitable mate rials having  a low non-ventilated retention of 15 to 50%. 2. The coaxial cigarette as set forth in claim 1, characterized in that said filter (10) comprises three longitudinal segments, namely a mouth-end segment (11) having low retention, a middle segment (12) having high retention and a tobacco end coaxial filter segment (13).d) the ratio of the resistance to draw of said rod core (22) to the resistance t o draw of said rod jacket is greater than unity and preferably in the range of 2 to 4. 3. The coaxial cigarette as set forth in claim 1 and 2 comprising a filter coaxial segment (13), characterized by at least one of the following features: - the resistance to draw of said jacket element (14) is in the range of 80 to 150 mm WC, - the resistance to draw of said core element (15) is in the range of 160 to 450 mm WC, - a cellulose acetate jacket element (14) has a single denier of 2.5 to 5 dpf, - a cellulose acetate core element (15) has a single denier of 1.5 to 2.1 dpf. 4. The coaxial cigarette as set forth in claim 2 or claim 3, characterized in th at said middle filter segment (12) consists of a filter material such as paper, Crest or preferably cellulose acetate, features a resistance to draw of 30 to 100 mm WC, preferably 50 to 60 mm WC, and that its single denier for the cellulose acetate is in the range of 1 .5 to 5 dpf, preferably in the range of 1.5 to 2.1 dpf. 5. The coaxial cigarette as set forth in any of the claims 2 to 4, characterized in that said mouth-end segment (11) consists of a filter material such as paper, Crest or preferably cellulose acetate or is a hollow tip and features a resistance to draw of 0 to 50 mm WC, preferably 10 to 15 mm WC. 6. The coaxial cigarette as set forth in any of the claims 1 to 5 including a coaxial tobacco rod comprising at least one of said following features:  - the total rod resistance to draw is in the range of 30 to 100 mm WC, preferably 50 mm WC; - the air permeability of said rod jacket wrapping (24) is in the range of 15 to 300 CU, preferably 50 to 100 CU; - said rod jacket wrapping (24) contains combustion/glowing salts such as N a acetate or K citrate, preferably K citrate in a range of 1 to 2.5%; - said rod core wrapping (23) consists of sheet tobacco or cigarette paper having an air permeability of 0 to 50 CU, preferably 0 to 5 CU; - the taste-relevant tobaccos are arranged preferably in said rod jacket (21). 7. The coaxial cigarette as set forth in any of the claims 2 to 6, characterized in that said filter has an overall length of 21 to 31 mm, preferably 27 mm, including  - said mouth-end segment (11) having a length of 4 to 16 mm, preferably 11 to 13 mm, - said middle segment (12) having a length of 4 to 12 mm, preferably 5 to 7 mm and - said tobacco-end segment (13) having a length of 7 to 16 mm, preferably 8 t o 10 mm, the ventilation perforations (18) produced preferably by laser perforation or by use of pre-perforated filter wrapper being arranged in the portion of said middle segment (12) or more particularly in the portion of said mouth-end segment (11), when the length of said mouth-end segment (11) exceeds 11 mm, and the filter ventilation rate being in the range o f 50 to 85%. 8. The coaxial cigarette as set forth in any of the claims 1 to 7, characterized in that the diameter of said filter (10) is in the range of 7 to 9 mm, preferably 7.8 mm, said core element (15) of said coaxial filter segment (13) having a diameter of 4 to 6 mm and preferably 5 to 6 mm. 9. The coaxial cigarette as set forth in any of the claims 1 to 8, characterized in that said tobacco rod (20) has a diameter in the range of 7 to 9 mm, preferably 7.8 mm, said rod core (22) having a diameter of 4 to 6 mm, preferably 5 to 5.6 mm. 10. The coaxial cigarette as set forth in any of the claims 1 to 9, characterized in that said coaxial filter segment (13) is non-ventilated.